CN106639329A - Steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method - Google Patents
Steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method Download PDFInfo
- Publication number
- CN106639329A CN106639329A CN201610904288.4A CN201610904288A CN106639329A CN 106639329 A CN106639329 A CN 106639329A CN 201610904288 A CN201610904288 A CN 201610904288A CN 106639329 A CN106639329 A CN 106639329A
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- Prior art keywords
- steel strand
- pressure
- tightening
- pretension
- strand wires
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Classifications
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
- E04G21/00—Preparing, conveying, or working-up building materials or building elements in situ; Other devices or measures for constructional work
- E04G21/12—Mounting of reinforcing inserts; Prestressing
- E04G21/121—Construction of stressing jacks
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- Engineering & Computer Science (AREA)
- Architecture (AREA)
- Mechanical Engineering (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Reinforcement Elements For Buildings (AREA)
Abstract
The invention discloses a steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method. The method includes the steps that single steel strands are stretched and drawn through a plurality of pre-tightening devices comprising oil cylinders and pistons; pre-tightening stretching-drawing operation is carried out; oil pressure is measured in real time; when all piston stretching cylinders achieve one stroke, if the pressure does not reach a pre-tightening force set value, automatic returning is carried out for next-stroke pre-tightening till the pressure reaches the set value; if the pre-tightening pressure of any steel strand reaches the set value, a pressure signal is transmitted to a control center through a pressure sensor, the control center controls an overflow valve to be started to maintain the pressure, and after the pre-tightening pressure of all the steel strands reaches the set value, oil is stopped from being supplied to the pre-tightening devices. The method has the advantages that as each pre-tightening jack is of a structure with one oil cylinder and multiple pistons, the integration degree is high, the function of simultaneously and automatically pre-tightening multiple steel strands can be achieved, and the working space is small; for extra-long steel strands, automatic stretching reversing of the jacks can be achieved, continuous pre-tightening is achieved, the speed is high, and the labor cost is low.
Description
Technical field
The present invention relates to a kind of civil engineering construction machinery and construction method, particularly a kind of steel strand group anchor inhaul cable is whole
The method of body formula automatic synchronization pretension.
Background technology
In the engineerings such as steel strand group anchor inhaul cable tensioning, post-tensioned prestressing tensioning, the lifting of large-scale component, traction, it is both needed to
First pretension is carried out to presstressed reinforcing steel or load muscle so that every presstressed reinforcing steel or load muscle stress are basically identical, then just can enter
Row integral tension and lifting, traction.The pretightening jack for using at present is front clip type jack, and it has following defect：
（1）Using front clip type jack pretension, can only a pretension, due between steel strand wires produce phase mutual friction, can lead
Cause each steel strand wires discontinuity.And because jack stroke is short, and steel strand wires and longer need repeatedly artificial to jack
Tune rope is opened, efficiency is low, hand labor intensity is big, work high above the ground, increase security risk；
External force is provided to jack with common oil pump, oil pump is manually operated, while ordinary jack does not possess displacement and tractive force
Deng data acquisition, entirely with artificial reading, artificial control, error is big, and risk is big.
The content of the invention
It is an object of the invention to provide a kind of can be used on steel strand group anchor inhaul cable, post-tensioned prestressing muscle, large-scale component
The engineering track cable pre-tightening apparatus such as lifting, traction, are capable of achieving the simultaneously independent automatic pretension of many steel strand wires, can to overlength steel strand wires
Realize that jack is opened automatically, the function such as continuous pretension, easy construction, efficiency high, pretightning force controls uniform steel strand wires group anchor
The method of automatic pretension.
The solution of the present invention is such：
A kind of method of steel strand group anchor inhaul cable monoblock type automatic synchronization pretension, it is characterised in that：Including step：
（1）Pre-tightening apparatus setting steps：Multiple steel strand wires bar numbers including oil cylinder, the pre-tightening apparatus tensioning on demand of piston are carried out
Configuration, each steel strand wires are individually connected with a pre-tightening apparatus, and by the pre-tightening apparatus tensioning of single steel strand is carried out；
（2）Many steel strand wires are while pretension step：To in step（1）In multiple pre-tightening apparatus for setting while providing identical pressure
The oil pressure of power so that each pre-tightening apparatus is moved in one direction simultaneously, carries out pretension tensioning operation；
（3）Pretightning force locks control strategy：Oil pressure is measured in real time, when whole pistons stretch cylinder reaches a stroke：If pressure
Pretightning force setting value is not reaching to, then control centre's control electromagnetic switch valve events automated backhaul carries out the pretension of next stroke,
Until pressure reaches setting value；If the preload pressure of any of which root steel strand wires reaches setting value during cylinder pretension is stretched
When, pressure signal is transferred to control centre by pressure sensor, and control centre's control overflow valve starts, and the root steel strand wires are corresponding
Pre-tightening apparatus cannot again stretch cylinder, and remaining corresponding pre-tightening apparatus of steel strand wires for being not reaching to pretightning force setting value works on,
Until the preload pressure of all of steel strand wires is reached after setting value, control centre's control electromagnetic switch valve events stop to pre-
Tight device fuel feeding.
More specifically technical scheme also includes：In the step（3）In, also prevent steel strand wires retraction step including backhaul：Arrange
The anchorage of anti-retraction, the anchorage is in backward stroke of the piston so that intermediate plate self-locking in the presence of steel strand wires gravity, prevents steel strand wires from returning
Contracting.
Further：In the step（3）In, also including the continuous pretension step of automated backhaul：Set in each pre-tightening apparatus
Automated tool anchorage is put, the automated tool anchorage pushes tool clamping piece return in backhaul by spring force, you can carry out next line
The pretension tensioning of journey.
It is an advantage of the invention that：
1st, many steel strand wires automatic pretension function simultaneously is capable of achieving, and working space is little；
2nd, overlength steel strand wires are capable of achieving with jack to open automatically, continuous pretension, speed is fast, and cost of labor is low.
Description of the drawings
Fig. 1 is one of the method for realizing the present invention and is embodied as schematic device.
Fig. 2 is the structural representation of oil cylinder 8 of Fig. 1 shown devices.
Fig. 3 is the A-A sectional views of Fig. 2.
Fig. 4 is the hydraulic power unit panel parts scheme of installation of Fig. 1 shown devices.
Fig. 5 is the structural representation of control valve group in Fig. 1 shown devices.
Reference is in figure：1st, steel strand wires, 2, back-moving spring, 3, single hole instrument anchor slab, 4, guide post, 5, movable top
Plate, 6, tool clamping piece, 7, oil return opening, 8, oil cylinder, 9, piston, 10, oil-in, 11, location-plate, 12, top board, 13, spike, 14,
Anchorage, 15, intermediate plate anticreep plate, 16, stretching bed seat, 17, preload unit installing space, 18, electronic box, 19, variable-frequency motor, 20, electricity
Magnetic reversal valve, 21, valve body, 22, pressure sensor, 23, oil-in, 24, oil return opening, 25, pressure gauge connection, 26, automatically controlled overflow
Valve, 27, oil filler 28, magnetic valve main valve, 29, punching set, 30, work clip sheet, 31, enter oil cylinder hydraulic oil path 32, oil return
Cylinder hydraulic oil path.
Specific embodiment
The step of the present invention includes：
（1）Pre-tightening apparatus setting steps：Multiple steel strand wires bar numbers including oil cylinder, the pre-tightening apparatus tensioning on demand of piston are carried out
Configuration, each steel strand wires are individually connected with a pre-tightening apparatus, and by the pre-tightening apparatus tensioning of single steel strand is carried out；
（2）Many steel strand wires are while pretension step：To in step（1）In multiple pre-tightening apparatus for setting while providing identical pressure
The oil pressure of power so that each pre-tightening apparatus is moved in one direction simultaneously, carries out pretension tensioning operation；
3）Pretightning force locks control strategy：Oil pressure is measured in real time, when whole pistons stretch cylinder reaches a stroke：If pressure does not have
Have and reach pretightning force setting value, then control centre's control electromagnetic switch valve events automated backhaul carries out the pretension of next stroke, directly
Setting value is reached to pressure；If when the preload pressure of any of which root steel strand wires during stretching cylinder pretension reaches setting value,
Pressure signal is transferred to control centre by pressure sensor, and control centre's control overflow valve starts, and the root steel strand wires are corresponding pre-
Tight device cannot again stretch cylinder, and remaining corresponding pre-tightening apparatus of steel strand wires for being not reaching to pretightning force setting value works on, directly
Preload pressure to all of steel strand wires is reached after setting value, control centre's control electromagnetic switch valve events, is stopped to pretension
Device fuel feeding.
In the step（3）In, also prevent steel strand wires retraction step including backhaul：The anchorage of anti-retraction is set, the anchorage
In backward stroke of the piston so that intermediate plate self-locking in the presence of steel strand wires gravity, prevent steel strand wires from bouncing back.
In the step（3）In, also including the continuous pretension step of automated backhaul：In each pre-tightening apparatus, automated tool is set
Anchorage, the automated tool anchorage pushes tool clamping piece return in backhaul by spring force, you can carry out the pre- anxiety of next stroke
Draw.
Below according to a concrete device for implementing the present invention, the present invention is described in detail：
Implement the present invention composition system as shown in figure 1, be provided with multi-piston type pretightening jack, automated tool anchor, hydraulic power unit,
Overall control center, intermediate plate anticreep plate, by overall control center instruction is sent, and hydraulic power unit drives pretightening jack to realize that pretension works.
Top board 12, stretching bed seat 16 and spike 13 are interconnected to form support frame structure, and the left end of the top board 12 is fixed with monoblock type
The single pretightening jack of multi-cylinder, the described single pretightening jack of monoblock type multi-cylinder includes oil cylinder 8 and piston 9, such as Fig. 2,3 institutes
Show, the oil cylinder 8 is provided with 7 piston holes（Note：Piston hole number can be arranged flexibly according to actual needs）, each device of piston 9
The structure of overall 7 pistons is constituted in piston hole；The piston 9 is the piston with through hole, and punching set is socketed with its through hole,
The punching set is fixed on oil cylinder 8, forms piston 9 relative to the mobile structure of oil cylinder 8 and punching set, the group in each piston hole
Part is combined into a preload unit；It is provided with the wall of oil cylinder 8 and connects entering oil cylinder hydraulic oil path 31 and connecting each for each piston
The oil return cylinder hydraulic oil path 32 of piston, constitutes each piston while the structure stretched out or bounce back, enters oil cylinder hydraulic oil path
Oil-in 10 connect hydraulic power unit with the oil return opening 7 of oil return cylinder hydraulic oil path；The single pretension of the monoblock type multi-cylinder is very heavy
The left end on top is connected with single hole instrument anchor slab 3, and the single hole instrument anchor slab 3 is provided with the hole that single steel strand passes through, it is ensured that steel is twisted
Line passes through punching set, single hole instrument anchor slab 3；Each single hole left end of the single hole instrument anchor slab 3 is to coordinate with work clip sheet
Hole；The left end of the stretching bed seat 16 is connected with anchorage 14, and the anchorage 14 is provided with the hole that single steel strand passes through, it is ensured that steel strand wires
Pass through, be the hole that lower work clip sheet coordinates in each single hole of the left end of anchorage 14.
The left end of the single hole instrument anchor slab 3 is connected with movable panel 5, and the movable panel 5 is socketed on and is fixed on single hole
Guide plate 4 on instrument anchor slab 3, is provided with elastic force apparatus between guide post 4 and movable panel 5, and the elastic force apparatus are to the right
Elastic force promote movable panel 5 to withstand on the left side of work clip sheet, the elastic force apparatus of the present embodiment are left in single hole instrument anchor slab 3
End is fixed with the guide post 4 stretched out to left end, and guide post 4 is socketed with back-moving spring 2, and the movable end of back-moving spring 2 withstands socket
In the movable panel 5 of guide post 4, the elastic force to the right of back-moving spring 2 promotes movable panel 5 to withstand on the left side of work clip sheet.
The left end of the anchorage 14 has been connected with intermediate plate anticreep plate 15, and it is provided with through hole and passes through for steel strand wires 1.Install
Work clip sheet 30 on anchorage 14 is between anchorage 14 and intermediate plate anticreep plate 15.The use of the intermediate plate anticreep plate 15 be
Prevent the intermediate plate being arranged on anchorage from releasing during pretension tensioning.
As shown in Figure 4,5, the hydraulic power unit includes fuel tank, electronic box 18, control valve group, pressure sensor 22, the control
Valve group processed includes valve body 21, solenoid directional control valve 20, automatically controlled overflow valve 26, and the control valve group is provided with oil-in 21, oil return opening
24, oil-in each oil-in 21, oil return opening 24 are respectively provided with a solenoid directional control valve；The pressure sensor 22 and described
Automatically controlled overflow valve 26 is arranged on oil-feed oil circuit.
Said apparatus are when pretension is constructed, and the method using present invention control is as follows：
1st, complete group anchor to arrange after device step, starting device after pretightning force setting value be input into by the touch-screen of overall control center,
Equipment works as follows automatically：
2nd, pretension：Overall control center sends instruction, and pretightening jack fuel feeding is given in the action of solenoid directional control valve 20, and hydraulic oil is from pretension thousand
Jin jacking hydraulic fluid port 10 sequentially enters each pretension working cell tensioning oil cylinder, and each pretension working cell piston 9 extends, single hole moveable anchor
Plate 3 tenses lax steel strand wires, while pressure sensor 22 is real with the tool clamping piece 6 of steel strand wires 1 is clamped together to reach
When measured pressure value and pressure data is transmitted to overall control center.When piston 9 stretches cylinder reaches a stroke, such as pressure is also less than
Up to position pretightning force setting value, then automated backhaul carries out the pretension of next stroke, when piston 9 drives single hole instrument 3 backhaul of anchor slab,
The tool clamping piece 6 of single hole automated tool anchor resets in the presence of back-moving spring 2, is that next stroke pretension prepares.Stretch in piston 9
During cylinder, the intermediate plate anticreep plate 15 installed in the front end of anchorage 14 can prevent intermediate plate from releasing；In backward stroke of the piston, the intermediate plate of anchorage 14 exists
Self-locking in the presence of steel strand wires gravity, prevents steel strand wires from bouncing back.So move in circles, until pretightning force reaches setting value.When
When a certain steel strand wires pretightning force reaches pretightning force setting value, pressure information is transferred to control centre by pressure sensor, control
Center sends instruction, and automatically controlled overflow valve 26 starts, and the pretension working cell cannot be pressurized again, and the piston 9 of the unit quits work,
Remaining corresponding pretension working cell of steel strand wires for not reaching pretension setting power works on, so until all steel strand wires reach
To pretightning force setting value, overall control center sends instruction, and the action of solenoid directional control valve 20 stops to pretightening jack fuel feeding.
Claims (3)
1. a kind of method of steel strand group anchor inhaul cable monoblock type automatic synchronization pretension, it is characterised in that：Including step：
（1）Pre-tightening apparatus setting steps：Multiple steel strand wires bar numbers including oil cylinder, the pre-tightening apparatus tensioning on demand of piston are carried out
Configuration, each steel strand wires are individually connected with a pre-tightening apparatus, and by the pre-tightening apparatus tensioning of single steel strand is carried out；
（2）Many steel strand wires are while pretension step：To in step（1）In multiple pre-tightening apparatus for setting while providing identical pressure
The oil pressure of power so that each pre-tightening apparatus is moved in one direction simultaneously, carries out pretension tensioning operation；
（3）Pretightning force locks control strategy：Oil pressure is measured in real time, when whole pistons stretch cylinder reaches a stroke：If pressure
Pretightning force setting value is not reaching to, then control centre's control electromagnetic switch valve events automated backhaul carries out the pretension of next stroke,
Until pressure reaches setting value；If the preload pressure of any of which root steel strand wires reaches setting value during cylinder pretension is stretched
When, pressure signal is transferred to control centre by pressure sensor, and control centre's control overflow valve starts, and the root steel strand wires are corresponding
Pre-tightening apparatus cannot again stretch cylinder, and remaining corresponding pre-tightening apparatus of steel strand wires for being not reaching to pretightning force setting value works on,
Until the preload pressure of all of steel strand wires is reached after setting value, control centre's control electromagnetic switch valve events stop to pre-
Tight device fuel feeding.
2. the method for steel strand group anchor inhaul cable monoblock type automatic synchronization pretension according to claim 1, it is characterised in that：
The step（3）In, also prevent steel strand wires retraction step including backhaul：The anchorage of anti-retraction is set, and the anchorage is in backward stroke of the piston
When so that intermediate plate self-locking in the presence of steel strand wires gravity, prevent steel strand wires from bouncing back.
3. the method for steel strand group anchor inhaul cable monoblock type automatic synchronization pretension according to claim 1, it is characterised in that：
The step（3）In, also including the continuous pretension step of automated backhaul：In each pre-tightening apparatus, automated tool anchorage is set, should be certainly
Power driven tools anchorage pushes tool clamping piece return in backhaul by spring force, you can carry out the pretension tensioning of next stroke.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610904288.4A CN106639329A (en) | 2016-10-18 | 2016-10-18 | Steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610904288.4A CN106639329A (en) | 2016-10-18 | 2016-10-18 | Steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106639329A true CN106639329A (en) | 2017-05-10 |
Family
ID=58855550
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610904288.4A Pending CN106639329A (en) | 2016-10-18 | 2016-10-18 | Steel-strand-group-anchoring-inhaul-cable-integrated automatic synchronous pre-tightening method |
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| Country | Link |
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| CN (1) | CN106639329A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018072589A1 (en) * | 2016-10-18 | 2018-04-26 | 柳州黔桥工程材料有限公司 | Automated and synchronized control system for bundled steel strand anchoring |
| CN113373820A (en) * | 2021-07-07 | 2021-09-10 | 浙江工业职业技术学院 | Bridge prestress tension construction method |
| CN113832866A (en) * | 2021-10-29 | 2021-12-24 | 杭州富锚机械有限公司 | Steel strand stretching device for prestressed anchorage device |
| CN114852903A (en) * | 2022-05-24 | 2022-08-05 | 柳州欧维姆机械股份有限公司 | Jack and take-up and pay-off device cooperative operation control method and system |
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| CN2435452Y (en) * | 2000-08-10 | 2001-06-20 | 柳州市建筑机械总厂 | Anchoring clamping element locking device |
| KR20040097857A (en) * | 2003-05-13 | 2004-11-18 | 이영환 | Simultaneous Multi-strand Jacking Machine Producing Uniform Prestressing Forces for all Simultaneously Jacked Tendons |
| CN202500342U (en) * | 2012-01-13 | 2012-10-24 | 柳州二千预应力有限公司 | Post-tensioned prestressing automatic tensioning system |
| CN103526948A (en) * | 2013-10-24 | 2014-01-22 | 柳州黔桥工程材料有限公司 | Control method of intelligent tension system and intelligent tension system |
| CN103741953A (en) * | 2013-12-20 | 2014-04-23 | 广西科技大学 | Automatic prestress tensioning control system |
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- 2016-10-18 CN CN201610904288.4A patent/CN106639329A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2435452Y (en) * | 2000-08-10 | 2001-06-20 | 柳州市建筑机械总厂 | Anchoring clamping element locking device |
| KR20040097857A (en) * | 2003-05-13 | 2004-11-18 | 이영환 | Simultaneous Multi-strand Jacking Machine Producing Uniform Prestressing Forces for all Simultaneously Jacked Tendons |
| CN202500342U (en) * | 2012-01-13 | 2012-10-24 | 柳州二千预应力有限公司 | Post-tensioned prestressing automatic tensioning system |
| CN103526948A (en) * | 2013-10-24 | 2014-01-22 | 柳州黔桥工程材料有限公司 | Control method of intelligent tension system and intelligent tension system |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018072589A1 (en) * | 2016-10-18 | 2018-04-26 | 柳州黔桥工程材料有限公司 | Automated and synchronized control system for bundled steel strand anchoring |
| CN113373820A (en) * | 2021-07-07 | 2021-09-10 | 浙江工业职业技术学院 | Bridge prestress tension construction method |
| CN113832866A (en) * | 2021-10-29 | 2021-12-24 | 杭州富锚机械有限公司 | Steel strand stretching device for prestressed anchorage device |
| CN114852903A (en) * | 2022-05-24 | 2022-08-05 | 柳州欧维姆机械股份有限公司 | Jack and take-up and pay-off device cooperative operation control method and system |
| CN114852903B (en) * | 2022-05-24 | 2023-09-12 | 柳州欧维姆机械股份有限公司 | Control method and system for cooperative operation of jack and coiling and uncoiling device |
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Application publication date: 20170510 |